Bushing cover

ABSTRACT

A generally elbow-shaped bushing muff or cover is utilized to provide an insulating cover for an angular connection between one or more conductors and a bushing terminal of a transformer. The muff is formed of a flexible insulating body consisting of a pair of generally U-shaped arm portions extending from a corner. One of the U-shaped arm portions has a bight portion readily mountable over the bushing terminal and has leg portions wrappable about each other and the terminal. The other of the Ushaped arm portions has a bight portion mountable over the conductor or conductors and has leg portions wrappable about each other and the conductor or conductors.

United States- Patent 1191 Paschen BUSHING COVER [75] Inventor: AllenJoseph Paschen, Baraboo,

Wis.

[73] Assignee: Webster Electric Company, Inc.,

Racine, Wis,

[22] Filed: Aug. 11, 1972 [21] App]. No.: 279,937

[52]- us. c1 174/138 F, 15 0/52 R, 174/5 R [51] 1111. c1. 11011) 17/00[58] Field of Search 174/5 R, 77 s, 92,

174/136, 138 F, 139,71 R; 29/428; 150/52 R, 52 G; 339/26, 116 R, 116 C;285/45, 47,

[56] 1 References Cited UNITED STATES PATENTS 738,250 9/1903 Stanley174/136 X 1,180,729 4/1916 Marshall 174/5 R 1,967,014 7/1934 Taverner174/5 R [4 Oct. 16, 1973 2,891,101 6/1959 Koliss 174/5 R X 3,019,2871/1962 Newcomb, Jr. et al 174/5 R X- 3,328,511 6/1967 Cagle et a1. 174/5R X Primary Examiner-Laramie E. Askin Attorney-Richard D. Mason et a1.

[5 7] ABSTRACT A generally elbow-shaped bushing muff or cover isutilized to provide an insulating cover for an angular connectionbetween one or more conductors and a bushing terminal of a transformer.The muff is formed of a flexible insulating body consisting of a pair ofgenerally U-shaped arm portions extending from a corner. One of theU-shaped arm portions has a bight portion readily mountable over thebushing terminal and has leg portions wrappable about each other and theter- I minal. The other of the U-shaped arm portions has a.

bight portion mountable over the conductor or conductors and has legportions wrappable about each other and the conductor or conductors.

11 Claims, 9 Drawing Figures Patented Oct 16, 1973 3 Sheets-Sheet 1Patented Oct. 16, 1973 3 Sheets-Sheet 3 BUSHING COVER This inventionrelates to a bushing muff, and more particularly, to a new and improvedflexible bushing muff adjustably mountable about angular connectionsbetween at least one conductor and a bushing terminal of a transformer.

Distribution transformers normally have a bushing terminal projectingfrom a wall of the transformer so that one or several secondary leads orconductors can be coupled to the transformer. In most instances, theconnection between the secondary leads and the bushing terminal is notonly angular in configuration but also is exposed, causing a shockhazard both to humans and animals. In order to prevent or eliminate thisshock hazard, the exposed connection must be covered with insulatingmaterial.

.One type of commercially available insulating cover or protectorincludes a solid tubular elbow device which for installation requiresthe disconnection of the leads from the bushing terminal, the guiding orforcingof the leads through the device for reconnection of the leads,and the movement of the device over the bushing terminal. The requireddisconnection of the leads from the bushing terminal for installationmakes this type of device unsatisfactory when additional leads are to becoupled to the terminal. Moreover, this type of device is normally soinflexible that virtually every installation requires a different sizeor shaped cover and is not readily usable when a plurality of leads areconnected to a single terminal.

Another type of available protective cover is installable with thesecondary leads connected to the bushing terminal. However, this type ofprotective cover normally can only accommodate a limited number of sizedleads and bushings, and does not completely enclose the connectionbetween the leads and the bushing terminal so that extensive taping mustbe done for the completion of the protection.

Still other covering devices have also been found unsatisfactory becausethey are not usable when a plurality of leads are connected to theterminal, are only usable with specific sized leads and/or bushings, orare not usable to cover angular connections.

Accordingly, objects of the present invention are to provide a new andimproved bushing muff that covers and insulates angular connectionsbetween secondary leads and bushing terminals on a transformer; isusable with various sized leads and bushing; is installable withoutthedisconnection of the secondary leads from the bushing terminal;substantially encloses the connection between the leads and the terminalwithout extensive supplemental taping; and is usable even thougha'multiplicity of secondary leads are coupled to the bushing terminal. I

In accordance with these and many other objects, one embodiment of thepresent invention comprises a flexible insulating body forming agenerally elbowshaped bushing muff for use in covering an angularconnection between at least one conductor and a bushing terminal of atransformer. The body of the bushing muff includes first and secondgenerally U-shaped arm portions that are joined together at a corner.The first U-shaped arm portion has a bight portion readily mountableover the bushing terminal of the transformer and is severable alongspecified cut lines so as to fit over various sized bushing terminals.The second U-shaped arm portion also has a bight portion that ismountable over the conductor coupled to the bushing terminal. Each ofthe U-shaped arm portions has a pair of legs extending from the bightportions which legs are wrappable and maintained about the terminal andconductor, respectively, so as to complete the insulation of the angularconnection.

Many other objects and advantages of the present invention will becomeapparent from considering the following detailed description inconjunction with the drawings in which:

FIG. I is a perspective view of a bushing muff embodying the presentinvention;

FIG. 2 is a perspective view of the bushing muff of FIG. 1 partiallyinstalled about a transformer bushing terminal connection;

FIG. 3 is a perspective view of the bushing muff of FIG. 1 after beingcompletely installed about the transformer bushing connection;

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a side elevational view of the bushing muff of FIG. I;

FIG. 7 is an end view of the bushing muff of FIG. 6;

FIG. 8 is another side elevational view of the bushing muff of FIG. 1;and

FIG. 9 is a bottom view of the bushing muff of FIG. .6.

Referring now to FIG. 1, there is shown a bushing muff or covergenerally indicated as 20 embodying the present invention. The bushingmuff 20 includes a generally U-shaped arm portion 22 having a bightportion 24 and a pair of legs or flaps 26 and 28 and a generallyU-shaped arm portion 30 having a bight portion 32 and a pair of legs orflaps 34 and 36. The arm portions 22 and 30 extend from or join togetherat a comer 38 so as to form a substantially elbow-shaped body 40.

As indicated by an arrow 42, the muff 20, and more particularly, thebight portion 24, is mountable or placeable over a bushing terminal 44projecting or extending from a wall 46 of a transformer or the like.When the bight portion 24 is positioned about the bushing terminal 44 sothat the bushing terminal 44 extends into the corner 38 of the bushingmuff 20, the

bight portion 32 is positioned or mounted over or about a pair ofsecondary leads or conductors 48 and 50 angularly coupled to the bushingterminal 44. In order for the bushing muff 20 to insulate the angularconnection between the bushing terminal 44 and the conductors 48 and 50,the leg 26 is folded or wrapped about the bushing terminal 44 and theleg 28 is then folded or wrapped about the leg 26 and the bushingterminal'44. Likewise, the leg 34 extending from the bight portion 32 isbent around or wrappedabout the conductors 48 and 50 and then the leg 36is wrapped about the leg 34 and the conductors 48 and 50.

More specifically and with reference to FIGS. I through 5, once thebushing muff 20 has been positioned over the bushing tenninal 44, theleg 26 extending from one side of the bight portion 24 is wrapped aboutthe bushing terminal 44 in the direction indicated by an arrow 52. Whilethe leg 26 is held or maintained in its wrapped position about thebushing terminal 44, the leg 28 extending from the other side of thebight portion 24 is folded or wrapped about the leg 26 and the bushingterminal 44 as indicated by an arrow 54 in FIG. 1. Similarly, the leg 34extending from one side of the bight portion 32 is bent around orwrapped about the conconductors 48 and 50 in the general directionindicated by an arrow 56 in FIG. 1. While the leg 34 is held in placeabout the conductors 48 and 50, the leg 36 extending from the other sideof the bight portion 32 is wrapped about the leg 34 and the conductors48 and 50 asindicated by an arrow 58.

After the legs 26 and 28 have been wrapped about each other and thebushing terminal 44, a cable strap 60 or other securing device, such asa piece of tape or the like, is placed about the bight portion 24 andthe- "folded legs 26 and 28. In this manner and as best seen in FIGS. 2and 4, a generally tubular pocket or truncated substantially conicalenvelope 62 is formed about and insulates a substantial portion of thebushing terminal 44. Although the illustrated bushing terminal 44 is aspade-type bushing terminal having a bushing portion 64 and a terminalconnector or spade 66 to which is coupled the pair of conductors 48 and50 by appropriate fastening devices 68 and 70, respectively, the bushingmuff can be utilized with various other types of bushing terminals, suchas a lug or regular type of bushing terminal, and with various numbersof conductors connected thereto. Moreover, since the bushing muff 20 isa flexible structure, the legs'26 and 28 can be wrapped tightly orloosely so that the end portion of the tubular pocket or envelope 62fits snugly about the bushing 64 even though the bushing 64 may vary insize or diameter.

Once the arm portion 22 is secured about the bushing terminal 44, asdescribed above and shown in FIG. 2, and the legs 34 and 36 have beenwrapped about each other and the conductors 48 and 50, a cable strap 72or the like is placed about the wrapped legs 34 and 36 and the bightportion 32 to secure the legs 34 and 36 in the wrapped position. As bestseen in FIGS. 3 and 5, the wrapped legs 34 and 36 and the bight portion32 of the arm 30 form a generally tubular pocket or truncatedsubstantially conical envelope 74 which fits snugly about the conductors48 and 50. The securing of the legs 34 and 36 about the conductors 48and 50 completes the insulation of the bushing muff 20 about the angularconnection between the bushing terminal 44 and the conductors 48 and 50so that a generally tubular insulated elbow-shaped covering or body 75is formed about the connection.

Of course, the number or sizes of the conductors 48 or 50 coupled to thebushing terminal 44 can vary depending on the individual transformerinstallation and- /or requirements. Advantageously, notwithstanding thenumber or size of the conductors 48 and 50, the same bushing muff 20 canbe utilized as a protective covering for the connection. If a lessernumber of or smaller conductors are coupled to the bushing terminal 44,the legs 34 and 36 would only have to be wrapped more tightly about eachother to provide the appropriate installation. On the other hand, iflarger or more conductors were utilized, the legs 34 and 36 would merelybe wrapped loosely so as to provide an appropriate fit about theconductors connected to the bushing terminal 44.

Moreover, as is readily apparent from FIGS. 1 through 5, by simplyremoving the straps 60 and 72 from the arm portions 22 and 30,respectively, the bushing muff 20 is readily removable from about theconnection between the conductors 48 and 50 and the bushing terminal 44and either of the conductors 48 or 50 can be disconnected from theterminal connector 66 without disconnecting or disturbing the otherconductor. In addition, more leads can be coupled to the terminalconnector 66 without the disconnection of either of the conductors 48and 50. Thereafter, the same bushing muff 20 can be replaced about thenew connection in the same manner as described above.

The actual construction of the bushing muff 20 is best seen by referringto FIGS. 6 through 9. The body 40 of the bushing muff 20 issubstantially formed of a flexible molded rubber, and each of the armportions 22 and 30 are generally U-shaped and have arcuate end surfaces76 and 78, respectively. The bight portion 24 of the arm 22 has a numberof ridges 80, 82 and 84 and the bight portion 32 of the arm 30 has apair of ridges 86 and 88 which lend strength to the arm portions 22 and30 and aid in the proper wrapping and securing of the legs 26, 28, 34and 36. The arm portions 22 and 30 join together at the corner 38 toform a pocket or cav ity 89 into which the terminal connector 66 isfittable.

The leg 26 extending from the bight portion 24 has a generallycurvilinear edge portion 90 that extends generally away from the corner38 and towards the arcuate surface 76 of the arm 22 to form a roundedtip 92 for the end of the-leg 26. The leg or flap 28 extending from theother side of the bight portion 24 is somewhat longer than the leg 26and has generally straight edges 94 and 96. Since the leg 26 is shorterthan the leg 28 and is rather pointed at its end 92, the leg 26 iseasily wrappable about the bushing terminal 44 and under the leg 28. '0

The leg 34 extending from one side of the bight portion 32 is relativelyshort in length and has edge por tions 98 and 100. The edge surface 98extends generally parallel and relatively close to the edge surface 94of the flap 28 so as to form or define a rather small or narrow slit oropen area 102. The leg 36 extending from the other side of the bightportion 32 is generally longer than the leg 34 and has a rather straightedge 104. Since the leg 34 is shorter than the leg 36, the leg 36 iseasily wrappable about the conductors 48 and 50 and the wrapped leg 34.

A side edge 106 of the leg 36 is generally curvilinear and extendsgenerally parallel and relatively close to the edge surface 90 of theleg 26 to form or define a rather small or narrow slit or open area 108.By having the slits or open areas 102 and 108 formed between the legs 28and 34 and the legs 26 and 36, respectively, the various legs 26, 28, 34and 36 are readily wrappable about the bushing terminal 44 and theconductors 48 and 50 so that the bushing mufi 20 is easily installedabout the angular connection between the bushing terminal 44 and theconductors 48 and 50. Moreover, the orientation of the relatively narrowslits 102 and 108 relative to each other assures that when the flap 28is wrapped about the flap 26 and the flap 36 is wrapped about the flap34 little or no apertures will remain through which access might be hadto the exposed portions of the connection between the conductors 48 and50 and the bushing terminal 44; thus eliminating any possible shockhazard.

In addition, the curvilinear or arcuate edges 78 and 106 of the flap 36tend to form the base and top of the truncated substantially conicalenvelope 74 resulting from or formed by the wrapping of the flap 36 overthe flap 34 and the conductors 48 and 50. This conical form of theenvelope 74 assures a snug fit over the conductors 48 and 50 even thoughthe spade 66 and the connecting lug or fasteners 68 and 70 may beconsiderably bulkier than the conductors 48 and 50. Likewise, thecurvilinear edge 76 of the flaps 26 and 28 provides the generallyconical shape of the envelope 62 when the flap 28 is wrapped about theflap 26, the bushing 64 and the spade 66. This assures that the envelope62 will snugly fit on the bushing 64 even if the connections between thebushing terminal 44 and the conductors 48 and 50 are somewhat bulky.

Extending about the arm portion 22 are a pair of indicating lines or cutlines 110 and 112. The indicating lines 110 and 112 indicate where thelegs 26 and 28 and the bight portion 24 should be severed if varioussized bushing terminals are being covered by the bushing muff 20. Forexample, if the bushing terminal utilized is not as long as theillustrated bushing terminal 44, the arm portion 22 can be severed alongthe indicating line 110 prior to the installation of the bushing muffabout the bushing terminal. Similarly, if the bushing terminal issubstantially shorter than the illustrated bushing terminal 44, the armportion 22 can be severed along the indicating line 1 12. In eithercase, the end of the bight portion 24 is still defined by the ridge 82or the ridge 80.

While the present invention has been described in connection with thedetails of one illustrative embodiment thereof, it should be understoodthat these details are not intended to be limitive of the inventionexcept insofar as set forth in the accompanying claims.

What is claimed and desired to be secured by Letters Patent of the U.S.is:

1. A flexible insulating body for forming a generally elbow-shaped muffover an angular connection between at least one conductor and a bushingterminal of a transformer, said body comprising first and secondgenerally U-shaped arm portions extending from a corner, said first armportion having a first bight portion mountable over said bushingterminal and having first and second generally flexible legs extendinggenerally parallel to each other away from said first bight portion onopposite sides of said bushing terminal, said first leg being wrappableabout said bushing terminal and said second leg being wrappable aboutsaid first leg and said bushing terminal,.and said'second arm portionhaving a second bight portion mountable over said conductor and havinggenerally flexible third and fourth legs extending generally parallel toeach other away from said second bight portion on opposite sides of saidconductor, said third leg being wrappable about said conductor and saidfourth leg being wrappable about said third leg and said conductor.

2. The muff as set forth in claim 1 wherein said third leg is shorterthan said fourth leg.

3. The muff as set forth in claim 1 wherein said first leg is shorterthan said second leg.

4. The muff as set forth in claim 1 wherein said first bight portion andsaid first and second legs have indicating means along which said firstarm portion is severable in order to propertly fit about said bushingtera bushing terminal of transformer, said cover comprising:

a generally elbow-shaped body portion having first and secondsubstantially U-shaped arms extending from a corner, said first armhaving a first bight portion mountable over said bushing terminal andfirst and second generally flexible flap means extending from the firstbight portion generally parallel to each other, said first flap meansbeing wrappable about said bushing terminal and said second flap meansbeing wrappable about said first flap means and said bushing terminal,said second arm having a second bight portion mountable over saidconductor and third and fourth generally flexible flap means extendingfrom the second bight portion generally parallel to each other, saidthird flap means being wrappable about said conductor and said fourthflap means being wrappable about said third flap means and saidconductor, and

securing means securing said second flap means about said first flapmeans and securing said fourth flap means about said third flap means.

7. The cover as set forth in claim 6 including a plurality of ridges onsaid first and second bight portions.

8. The cover as set forth in claim 6 wherein said body portion is formedof a molded rubber.

9. The cover as set forth in claim 6 wherein said-first and second armsand said comer form a pocket into which said connection is fittable.

10. A flexible insulating body for forming a generally elbow-shaped muffover an angular connection between at least one conductor and a bushingterminal of a transformer, said body comprising first and secondgenerally u-shaped arm portions extending from a corner, said first armportion having a first bight portion mountable over said bushingterminal and having first and second legs, said first leg beingwrappable about said bushing tenninal and said second leg beingwrappable about said first leg and said bushing terminal, said secondarm portion having a second bight portion mountable over said conductorand having third and fourth legs, said third leg being wrappable aboutsaid conductor and said fourth leg being wrappable about said third legand said conductor, said wrapping of said second leg about said firstleg and said fourth leg'about said third leg is facilitated by a firstslit formed between said first and fourth legs and a second slit formedbetween said second and third legs.

11. A flexible protective cover for encompassing an angular connectionbetween at least one conductor and a bushing terminal of a transformer,said cover comprising: I

a generally elbow-shaped body portion having first and secondsubstantially U-shaped arms extending from a comer, said first armhaving a first bight portion mountable over said bushing terminal andfirst and second flap means extending from the first bight portion, saidfirst flap means being wrappable about said bushing terminal and saidsecond flap means being wrappable about said first flap means and saidbushing terminal, said second arm having a second bight portionmountable over said conductor and third and fourth flap means extendingfrom the second bight portion, said third flap means being wrappableabout said conductor and said fourth flap means being wrappable aboutsaid third flap means and said conductor, and each of when said fourthflap means is wrapped about said third flap means, and

securing means securing said second flap means about said first flapmeans and securing said fourth flap means about said third flap means.

1. A flexible insulating body for forming a generally elbowshaped muffover an angular connection between at least one conductor and a bushingterminal of a transformer, said body comprising first and secondgenerally U-shaped arm portions extending from a corner, said first armportion having a first bight portion mountable over said bushingterminal and having first and second generally flexible legs extendinggenerally parallel to each other away from said first bight portion onopposite sides of said bushing terminal, said first leg being wrappableabout said bushing terminal and said second leg being wrappable aboutsaid first leg and said bushing terminal, and said second arm portionhaving a second bight portion mountable over said conductor and havinggenerally flexible third and fourth legs extending generally parallel toeach other away from said second bight portion on opposite sides of saidconductor, said third leg being wrappable about said conductor and saidfourth leg being wrappable about said third leg and said conductor. 2.The muff as set forth in claim 1 wherein said third leg is shorter thansaid fourth leg.
 3. The muff as set forth in claim 1 wherein said firstleg is shorter than said second leg.
 4. The muff as set forth in claim 1wherein said first bight portion and said first and second legs haveindicating means along which said first arm portion is severable inorder to propertly fit about said bushing terminal.
 5. The muff as setforth in claim 1 wherein said body is formed of flexible molded rubber.6. A flexible protective cover for encom-passing an angular connectionbetween at least one conductor and a bushing terminal of a transformer,said cover comprising: a generally elbow-shaped body portion havingfirst and second substantially U-shaped arms extending from a corner,said first arm having a first bight portion mountable over said bushingterminal and first and second generally flexible flap means extendingfrom the first bight portion generally parallel to each other, saidfirst flap means being wrappable about said bushing terminal and saidsecond flap means being wrappable about said first flap means and saidbushing terminal, said second arm having a second bight portionmountable over said conductor and third and fourth generally flexibleflap means extending from the second bight portion generally parallel toeach other, said third flap means being wrappable about said conductorand said fourth flap means being wrappable about said third flap meansand said conductor, and securing means securing said second flap meansabout said first flap means and securing said fourth flap means aboutsaid third flap means.
 7. The cover as set forth in claim 6 including aplurality of ridges on said first and second bight portions.
 8. Thecover as set forth in claim 6 wherein said body portion is formed of amolded rubber.
 9. The cover as set forth in claim 6 wherein said firstand second arms and said corner form a pocket into which said connectionis fittable.
 10. A flexible insulating body for forming a generallyelbow-shaped muff over an angular connection between at least oneconductor and a bushing terminal of a transformer, said body comprisingfirst and second generally U-shaped arm portions Extending from acorner, said first arm portion having a first bight portion mountableover said bushing terminal and having first and second legs, said firstleg being wrappable about said bushing terminal and said second legbeing wrappable about said first leg and said bushing terminal, saidsecond arm portion having a second bight portion mountable over saidconductor and having third and fourth legs, said third leg beingwrappable about said conductor and said fourth leg being wrappable aboutsaid third leg and said conductor, said wrapping of said second legabout said first leg and said fourth leg about said third leg isfacilitated by a first slit formed between said first and fourth legsand a second slit formed between said second and third legs.
 11. Aflexible protective cover for encompassing an angular connection betweenat least one conductor and a bushing terminal of a transformer, saidcover comprising: a generally elbow-shaped body portion having first andsecond substantially U-shaped arms extending from a corner, said firstarm having a first bight portion mountable over said bushing terminaland first and second flap means extending from the first bight portion,said first flap means being wrappable about said bushing terminal andsaid second flap means being wrappable about said first flap means andsaid bushing terminal, said second arm having a second bight portionmountable over said conductor and third and fourth flap means extendingfrom the second bight portion, said third flap means being wrappableabout said conductor and said fourth flap means being wrappable aboutsaid third flap means and said conductor, and each of said first,second, third and fourth flap means having at least one curvilinear edgeso that a first generally truncated substantially conical envelope isformed when said second flap means is wrapped about said first flapmeans and a second generally truncated substantially conical envelope isformed when said fourth flap means is wrapped about said third flapmeans, and securing means securing said second flap means about saidfirst flap means and securing said fourth flap means about said thirdflap means.